Early evaluation of irradiated parotid glands with intravoxel incoherent motion MR imaging: correlation with dynamic contrast-enhanced MR imaging

Table 4 Correlations between change rates of parotid IVIM and DCE MR parameters

R_IVIM-PARs	R_DCE-PARs	r	p value
R_ADC	R_MRE	0.103	0.550
	R_TTP	−0.048	0.780
	R_{Wash in Rate}	−0.006	0.973
R_D	R_MRE	0.191	0.264
	R_TTP	0.156	0.364
	R_{Wash in Rate}	0.181	0.290
R_D*	R_MRE	0.371	0.026^a
	R_TTP	0.396	0.017^a
	R_{Wash in Rate}	0.251	0.139
R_f	R_MRE	−0.079	0.647
	R_TTP	−0.238	0.162
	R_{Wash in Rate}	−0.116	0.500

IVIM Intravoxel incoherent motion, DCE dynamic contrast-enhanced, r Pearson correlation coefficient, R_IVIM-PARsand R_DCE-PARs are the change rates of IVIM and DCE MR parameters from pre-RT to post-RT, respectively, R_ADC, R_D, R_D*, R_f, R_MRE, R_TTPand R_{Wash in Rate} are the change rates of apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), maximum relative enhancement (MRE), time to peak (TTP) and Wash in Rate from pre-RT (2 weeks before radiotherapy) to post-RT (4 weeks after RT), respectively
^adenotes a significant correlation between the change rates of IVIM and DCE MR parameters

ISSN: 1471-2407